In electrophotographic machines which utilize plain paper, the image of an original document to be copied is placed onto a photoconductive surface which has been electrically charged. Light received from the image discharges the photoconductor according to the darkness of the original, thus leaving an image of the original on the photoconductor. The photoconductor is then developed, typically by the deposition of a black powder, and the developed image is transferred to plain copy paper. If the image of the original occupies an area of 8 1/2 .times. 11 inches and if the copy paper size is 8 1/2 .times. 11 inches, obviously the edges of the copy paper must be mated with the edges of the image in order to transfer the entire image without loss of information.
In prior art machines it has been customary to locate the leading edge of the image along the same line on the surface of the photoreceptor from copy to copy. Thus, a gate mechanism may be provided to release the copy paper to reach the photoreceptive surface in a manner designed to always mate the leading edge of the copy paper with that same line on the photoreceptor surface. However, it has been found that is some copier machine configurations wherein scanning optics are utilized and wherein the original document is referenced along a common edge or common edges, it is necessary to scan the document from the unreferenced edge toward the referenced edge. Because of that necessity, a 14-inch document is viewed three inches earlier during the scan than is the 11-inch document. As a consequence, the leading edge of the 14-inch image appears at the transfer station three inches sooner than the leading edge of the 11-inch image. As a result, the 14-inch copy paper must be released to mate with the leading edge of the 14-inch image sooner in the copy cycle than the 11-inch paper. The primary object of this invention is to provide a gate control mechanism which releases copy paper to mate with the leading edge of images at more than one position on the drum surface, thus providing a capability to variably locate the image leading edge at a number of particular drum locations.